Merge tag 'amd-drm-fixes-6.3-2023-03-29' of https://gitlab.freedesktop.org/agd5f/linux into drm-fixes

amd-drm-fixes-6.3-2023-03-29:

amdgpu:
- Two DP MST fixes

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
From: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230329220059.7622-1-alexander.deucher@amd.com

2 files changed, 58 insertions, 8 deletions

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
index e25e1b2bf194..8dc442f90eaf 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
@@ -212,6 +212,21 @@ bool needs_dsc_aux_workaround(struct dc_link *link)
 	return false;
 }
 
+bool is_synaptics_cascaded_panamera(struct dc_link *link, struct drm_dp_mst_port *port)
+{
+	u8 branch_vendor_data[4] = { 0 }; // Vendor data 0x50C ~ 0x50F
+
+	if (drm_dp_dpcd_read(port->mgr->aux, DP_BRANCH_VENDOR_SPECIFIC_START, &branch_vendor_data, 4) == 4) {
+		if (link->dpcd_caps.branch_dev_id == DP_BRANCH_DEVICE_ID_90CC24 &&
+				IS_SYNAPTICS_CASCADED_PANAMERA(link->dpcd_caps.branch_dev_name, branch_vendor_data)) {
+			DRM_INFO("Synaptics Cascaded MST hub\n");
+			return true;
+		}
+	}
+
+	return false;
+}
+
 static bool validate_dsc_caps_on_connector(struct amdgpu_dm_connector *aconnector)
 {
 	struct dc_sink *dc_sink = aconnector->dc_sink;
@@ -235,6 +250,10 @@ static bool validate_dsc_caps_on_connector(struct amdgpu_dm_connector *aconnecto
 	    needs_dsc_aux_workaround(aconnector->dc_link))
 		aconnector->dsc_aux = &aconnector->mst_root->dm_dp_aux.aux;
 
+	/* synaptics cascaded MST hub case */
+	if (!aconnector->dsc_aux && is_synaptics_cascaded_panamera(aconnector->dc_link, port))
+		aconnector->dsc_aux = port->mgr->aux;
+
 	if (!aconnector->dsc_aux)
 		return false;
 
@@ -662,12 +681,25 @@ struct dsc_mst_fairness_params {
 	struct amdgpu_dm_connector *aconnector;
 };
 
-static int kbps_to_peak_pbn(int kbps)
+static uint16_t get_fec_overhead_multiplier(struct dc_link *dc_link)
+{
+	u8 link_coding_cap;
+	uint16_t fec_overhead_multiplier_x1000 = PBN_FEC_OVERHEAD_MULTIPLIER_8B_10B;
+
+	link_coding_cap = dc_link_dp_mst_decide_link_encoding_format(dc_link);
+	if (link_coding_cap == DP_128b_132b_ENCODING)
+		fec_overhead_multiplier_x1000 = PBN_FEC_OVERHEAD_MULTIPLIER_128B_132B;
+
+	return fec_overhead_multiplier_x1000;
+}
+
+static int kbps_to_peak_pbn(int kbps, uint16_t fec_overhead_multiplier_x1000)
 {
 	u64 peak_kbps = kbps;
 
 	peak_kbps *= 1006;
-	peak_kbps = div_u64(peak_kbps, 1000);
+	peak_kbps *= fec_overhead_multiplier_x1000;
+	peak_kbps = div_u64(peak_kbps, 1000 * 1000);
 	return (int) DIV64_U64_ROUND_UP(peak_kbps * 64, (54 * 8 * 1000));
 }
 
@@ -761,11 +793,12 @@ static int increase_dsc_bpp(struct drm_atomic_state *state,
 	int link_timeslots_used;
 	int fair_pbn_alloc;
 	int ret = 0;
+	uint16_t fec_overhead_multiplier_x1000 = get_fec_overhead_multiplier(dc_link);
 
 	for (i = 0; i < count; i++) {
 		if (vars[i + k].dsc_enabled) {
 			initial_slack[i] =
-			kbps_to_peak_pbn(params[i].bw_range.max_kbps) - vars[i + k].pbn;
+			kbps_to_peak_pbn(params[i].bw_range.max_kbps, fec_overhead_multiplier_x1000) - vars[i + k].pbn;
 			bpp_increased[i] = false;
 			remaining_to_increase += 1;
 		} else {
@@ -861,6 +894,7 @@ static int try_disable_dsc(struct drm_atomic_state *state,
 	int next_index;
 	int remaining_to_try = 0;
 	int ret;
+	uint16_t fec_overhead_multiplier_x1000 = get_fec_overhead_multiplier(dc_link);
 
 	for (i = 0; i < count; i++) {
 		if (vars[i + k].dsc_enabled
@@ -890,7 +924,7 @@ static int try_disable_dsc(struct drm_atomic_state *state,
 		if (next_index == -1)
 			break;
 
-		vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.stream_kbps);
+		vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.stream_kbps, fec_overhead_multiplier_x1000);
 		ret = drm_dp_atomic_find_time_slots(state,
 						    params[next_index].port->mgr,
 						    params[next_index].port,
@@ -903,7 +937,7 @@ static int try_disable_dsc(struct drm_atomic_state *state,
 			vars[next_index].dsc_enabled = false;
 			vars[next_index].bpp_x16 = 0;
 		} else {
-			vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.max_kbps);
+			vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.max_kbps, fec_overhead_multiplier_x1000);
 			ret = drm_dp_atomic_find_time_slots(state,
 							    params[next_index].port->mgr,
 							    params[next_index].port,
@@ -932,6 +966,7 @@ static int compute_mst_dsc_configs_for_link(struct drm_atomic_state *state,
 	int count = 0;
 	int i, k, ret;
 	bool debugfs_overwrite = false;
+	uint16_t fec_overhead_multiplier_x1000 = get_fec_overhead_multiplier(dc_link);
 
 	memset(params, 0, sizeof(params));
 
@@ -993,7 +1028,7 @@ static int compute_mst_dsc_configs_for_link(struct drm_atomic_state *state,
 	/* Try no compression */
 	for (i = 0; i < count; i++) {
 		vars[i + k].aconnector = params[i].aconnector;
-		vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps);
+		vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps, fec_overhead_multiplier_x1000);
 		vars[i + k].dsc_enabled = false;
 		vars[i + k].bpp_x16 = 0;
 		ret = drm_dp_atomic_find_time_slots(state, params[i].port->mgr, params[i].port,
@@ -1012,7 +1047,7 @@ static int compute_mst_dsc_configs_for_link(struct drm_atomic_state *state,
 	/* Try max compression */
 	for (i = 0; i < count; i++) {
 		if (params[i].compression_possible && params[i].clock_force_enable != DSC_CLK_FORCE_DISABLE) {
-			vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.min_kbps);
+			vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.min_kbps, fec_overhead_multiplier_x1000);
 			vars[i + k].dsc_enabled = true;
 			vars[i + k].bpp_x16 = params[i].bw_range.min_target_bpp_x16;
 			ret = drm_dp_atomic_find_time_slots(state, params[i].port->mgr,
@@ -1020,7 +1055,7 @@ static int compute_mst_dsc_configs_for_link(struct drm_atomic_state *state,
 			if (ret < 0)
 				return ret;
 		} else {
-			vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps);
+			vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps, fec_overhead_multiplier_x1000);
 			vars[i + k].dsc_enabled = false;
 			vars[i + k].bpp_x16 = 0;
 			ret = drm_dp_atomic_find_time_slots(state, params[i].port->mgr,
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h
index 97fd70df531b..1e4ede1e57ab 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h
@@ -34,6 +34,21 @@
 #define SYNAPTICS_RC_OFFSET        0x4BC
 #define SYNAPTICS_RC_DATA          0x4C0
 
+#define DP_BRANCH_VENDOR_SPECIFIC_START 0x50C
+
+/**
+ * Panamera MST Hub detection
+ * Offset DPCD 050Eh == 0x5A indicates cascaded MST hub case
+ * Check from beginning of branch device vendor specific field (050Ch)
+ */
+#define IS_SYNAPTICS_PANAMERA(branchDevName) (((int)branchDevName[4] & 0xF0) == 0x50 ? 1 : 0)
+#define BRANCH_HW_REVISION_PANAMERA_A2 0x10
+#define SYNAPTICS_CASCADED_HUB_ID  0x5A
+#define IS_SYNAPTICS_CASCADED_PANAMERA(devName, data) ((IS_SYNAPTICS_PANAMERA(devName) && ((int)data[2] == SYNAPTICS_CASCADED_HUB_ID)) ? 1 : 0)
+
+#define PBN_FEC_OVERHEAD_MULTIPLIER_8B_10B	1031
+#define PBN_FEC_OVERHEAD_MULTIPLIER_128B_132B	1000
+
 struct amdgpu_display_manager;
 struct amdgpu_dm_connector;